[G,S]etWindowLongPtrW are not available on 32-bit Windows, where [G,S]etWindowLongW should be used instead.
The initial revision of #14945 imported the win package for calling and other Win32 API functions, which exported
the correct API depending on the platform. However, the same logic wasn't implemented when we removed
the win package dependency in a later revision, resulting in panics on Windows 10 x86 (there's no 32-bit Windows 11).
In this PR, we update the ipn/desktop package to use either [G,S]etWindowLongPtrW or [G,S]etWindowLongW
depending on the platform.
Fixes#15684
Signed-off-by: Nick Khyl <nickk@tailscale.com>
In this PR, we enable the registration of LocalBackend extensions to exclude code specific to certain
platforms or environments. We then introduce desktopSessionsExt, which is included only in Windows builds
and only if the ts_omit_desktop_sessions tag is disabled for the build. This extension tracks desktop sessions
and switches to (or remains on) the appropriate profile when a user signs in or out, locks their screen,
or disconnects a remote session.
As desktopSessionsExt requires an ipn/desktop.SessionManager, we register it with tsd.System
for the tailscaled subprocess on Windows.
We also fix a bug in the sessionWatcher implementation where it attempts to close a nil channel on stop.
Updates #14823
Updates tailscale/corp#26247
Signed-off-by: Nick Khyl <nickk@tailscale.com>
This PR adds a new package, ipn/desktop, which provides a platform-agnostic
interface for enumerating desktop sessions and registering session callbacks.
Currently, it is implemented only for Windows.
Updates #14823
Signed-off-by: Nick Khyl <nickk@tailscale.com>
